1. Field of the Invention
The invention relates to mobile communication devices, and particularly to a network access device, network connection establishing method, and a mobile communication system using the same.
2. Description of Related Art
Electronic communication networks have become more and more popular due to developments in communication technology. Some public places, such as sports arenas, shopping centers, are equipped with networks for users of mobile terminals. If a user of a mobile terminal wants to connect to a network wirelessly, the mobile terminal must first establish connection with and authenticate itself to an access point for connecting to the network, and then the mobile terminal can wirelessly communicate with the network via the access point. The authentication data of the mobile terminal is saved in the access point.
If the mobile terminal roams away from the coverage area of the access point, then the mobile terminal must establish a new connection with and authenticate itself to the next access point to continue communication with the network. This is inconvenient and puzzling for the user of the mobile terminal, and also increases operation loading of the network. A typically conventional method uses establishment of authentication connection between two different access points when the mobile terminal roams from one of the two access points to the other of the two access points. However, the mobile terminal still needs to experience the authentication process from each of the two access points. Therefore, it is nevertheless very inconvenient for the user of the mobile terminal.